Crystal structures and magnetic anisotropy properties of Ni-Mn-Ga martensitic phases with giant magnetic-field-induced strain

Several kinds of martensitic phases have been found in nonstoichiometric Ni-2 MnGa alloys in numerous recent studies. The structural, magnetic, and mechanical properties important for a giant magnetic-field-induced strain response in these alloys are presented. Depending on the martensite crystal structure Ni-Mn-Ga alloys are able to show a really giant (about 6% or 10%) strain response in a magnetic field less than I T.